Siemens SINAMICS S120 Equipment Manual page 149

Figure 3-47 Example: mounting plate with a drive line-up
When installing the module, you must ensure that the module seal is tight all round.
The cross-pieces must be sufficiently stable.
If required, we recommend that you reinforce the cross-pieces for the recesses.
In our example, the cross-pieces have been reinforced using brackets to EN 755-9.
Any means necessary can be used to secure the bracket to the insert plate.
Equipment Manual for Booksize Power Units
Equipment Manual, (GH2), 03/2006 Edition, 6SL3097-2AC00-0BP3
3.6 Smart Line Modules (5 kW and 10 kW) with external air cooling
Line Modules Booksize
3-83